What makes Libertarians and Tea Party people think that their way is so much better than our current system?

I am not asking this question to be hateful. I am truly curious and I'm trying, for once, to be open minded. Why do they believe that a smaller government would be better? Why are they so angry? To me, it seems like they want to overthrow our current system, replace it with a system of their own egos, and impose it on other people who might not want to live with their smaller federal government. Some people don't trust the states very much, as they don't have a very good track record (think slavery, Jim Crow), and when the federal government has less power...whites have more power and everyone else is left at their mercy...which can only lead to terrible things happening to all non-whites. I just think that it's better the evil you know, than the evil you don't know, and some of this Libertarian stuff sounds like anarchy, which I don't want if I'm outnumbered. If my rambling sounds ignorant to you, please educate me.